A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 5999-01-607-6418
NSN 5998-01-420-3424
NSN 7035-00-205-8739
NSN 5935-00-282-7967
NSN 5965-00-403-7497
NSN 6645-01-112-1095
NSN 5950-01-272-6145
NSN 5935-01-084-9848
NSN 4140-01-005-1860
NSN 5975-01-230-0863
NSN 6110-01-156-8441
NSN 5925-01-478-5111